Input devices, such as keyboards, mice, trackballs, touchpads, and touchscreens, are commonly used to control information technology devices. For example, keyboards, mice, trackballs, and touchpads are often used to control personal computers. On the other hand, touchscreens are widely used to control mobile telephones and tablet computers.
Some conventional input devices enable remote control of an information technology device. For example, a wireless mouse may be used to control a computer workstation. A wireless mouse typically includes circuitry to detect user movement of the mouse, generate signals representing the detected movement, and wirelessly transmit the signals to a computer workstation. Although a wireless mouse may work well in situations where a user remains at a desk or similar platform, the mouse may be awkward to use in situations where the user is mobile.
For instance, consider a situation where a user wishes to interact with an audience in a room while presenting a computer-generated presentation. If the user were to use a wireless mouse to control the computer, the user would need to remain at a platform, such as a table or a podium, to control the mouse. Thus, use of the wireless mouse would restrict the user's freedom to move about the room and interact with the audience.
Another example of conventional remote control of an information technology device is found in U.S. Pat. No. 6,704,000 to Carpenter et al. Carpenter teaches positioning a cursor within a predefined distance of an optical point on a projected image. Carpenter's teachings, however, are only applicable to situations where an image is projected on a projection surface, such as a wall.